[alsa-devel] [PATCH] ASoC: core: Add API for configuration of DAI BCLK ratio

[Liam Girdwood]

Some codec drivers when running in slave mode require that BCLK to sample rate ratio
is explicitly set by the machine driver as it may not be exactly rate * frame size.

Extend the DAI API by adding :-

int snd_soc_dai_set_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio);

Signed-off-by: Liam Girdwood <liam.r.girdwood at linux.intel.com>
---
 include/sound/soc-dai.h |  3 +++
 sound/soc/soc-core.c    | 16 ++++++++++++++++
 2 files changed, 19 insertions(+)

diff --git a/include/sound/soc-dai.h b/include/sound/soc-dai.h
index ae9a227..d8acf0c 100644
--- a/include/sound/soc-dai.h
+++ b/include/sound/soc-dai.h
@@ -105,6 +105,8 @@ int snd_soc_dai_set_clkdiv(struct snd_soc_dai *dai,
 int snd_soc_dai_set_pll(struct snd_soc_dai *dai,
 	int pll_id, int source, unsigned int freq_in, unsigned int freq_out);
 
+int snd_soc_dai_set_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio);
+
 /* Digital Audio interface formatting */
 int snd_soc_dai_set_fmt(struct snd_soc_dai *dai, unsigned int fmt);
 
@@ -131,6 +133,7 @@ struct snd_soc_dai_ops {
 	int (*set_pll)(struct snd_soc_dai *dai, int pll_id, int source,
 		unsigned int freq_in, unsigned int freq_out);
 	int (*set_clkdiv)(struct snd_soc_dai *dai, int div_id, int div);
+	int (*set_bclk_ratio)(struct snd_soc_dai *dai, unsigned int ratio);
 
 	/*
 	 * DAI format configuration
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 09e341d..8014839 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -3380,6 +3380,22 @@ int snd_soc_codec_set_pll(struct snd_soc_codec *codec, int pll_id, int source,
 EXPORT_SYMBOL_GPL(snd_soc_codec_set_pll);
 
 /**
+ * snd_soc_dai_set_bclk_ratio - configure BCLK to sample rate ratio.
+ * @dai: DAI
+ * @ratio Ratio of BCLK to Sample rate.
+ *
+ * Configures the DAI for a preset BCLK to sample rate ratio.
+ */
+int snd_soc_dai_set_bclk_ratio(struct snd_soc_dai *dai, unsigned int ratio)
+{
+	if (dai->driver && dai->driver->ops->set_bclk_ratio)
+		return dai->driver->ops->set_bclk_ratio(dai, ratio);
+	else
+		return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(snd_soc_dai_set_bclk_ratio);
+
+/**
  * snd_soc_dai_set_fmt - configure DAI hardware audio format.
  * @dai: DAI
  * @fmt: SND_SOC_DAIFMT_ format value.
-- 
1.8.1.2